It is desirable to pick up only a desired sound (a user's voice) during a telephone call or the like, and voice recognition, voice recording, or the like. However, a sound such as background noise, other than the desired sound, may also be present in any usage environment of a voice input device. Thus, there has been developed a voice input device having a noise removal function.
As a technique which removes a noise in a usage environment in which the noise is present, there has been known a technique which provides a microphone with sharp directivity, or a technique which detects a travel direction of sound waves using the difference between arrival times of the sound waves and removes noise through signal processing.
Further, in recent years, as electronic devices have been increasingly miniaturized, a technique which reduces the size of a voice input device has become important.